Background: Hypertension is a recognized cause of chronic kidney disease. Hypertension in blacks is most important because it is volume dependent and its ensuing renal complication. The widely accepted marker to assess renal function is creatinine and its estimated glomerular filtration rate. However, this is limited in assessing early renal impairment. This necessitate a need to evaluate other renal markers such as cystatin C. Objective: To measure and compare serum cystatin C and creatinine for early renal impairment among hypertensive patients on treatment. Methodology: A total of 48 hypertensive patients attending cardiology clinic for follow up were recruited in this study. Serum specimen were collected and assayed for creatinine and cystatin C. estimated glomerular filtration (eGFR) rate was calculated for the analytes. The two eGFR were compared in assessing renal function. Results: The BMI, Blood pressure and Abdominal circumference of the subjects were significantly higher than the controls (31.5±7.5kg/m 2 , 144/82mmHg and 102.3cm vs 26.1±4.3kg/m 2 , 116/80mmHg and 93cm) respectively Table 1. The hypertensives had a significantly higher serum levels of creatinine and cystatin C when compared with the controls (105µmol/L vs 88µmol/L and 2.9mg/L vs 1.1mg/L) respectively Table 2. Calculated estimated GFR for both serum creatinine and cystatin C were significantly lower among the subjects (89.1ml/min/1.73m 2 vs 110ml/min/1.73m 2 and 67.7ml/min/1.73m 2 vs 118ml/min/1.73m 2 ). Estimated GFR based on cystatin C was significantly lower than eGFR-Cr among the subjects (67.7ml/min/1.73m 2 vs 89.1ml/min/1.73m 2 ). There was a significant correlation between BMI and eGFR-Cr, abdominal circumference also had a significant correlation with fasting plasma glucose among the subjects and controls. Conclusion: serum levels of cystatin C appears to be a better predictor of GFR among hypertensive patients.